Question: Solve the equation. $ 18 + k = 30$ $k=$
Solution: Subtract $18$ from both sides: 18 − 18 + k k = = 30 − 18 30 − 18 \begin{eqnarray} \\ 18& + &k &= &30 \\ \\ {-18}& & & &{-18} \\\\ &&k &= &30 {- 18}\end{eqnarray} Simplifying, we get: $ k = 12$